What does scanning resolution actually do?
Here are several scanning resolutions from the same photograph. This 6×4 inch photo was scanned at 33 dpi. Since 6×33=198 and 4×33=132, then the image comes out 190×129 pixels (it was cropped just inside its edges). This image was scanned at 100 dpi. The higher resolution shows considerably more detail, but also magnifies the image size on screen. Video image size of a given original area depends only on resolution (not true for printers). The scan was cropped to a 356×280 image, because a 6×4 inch photo scanned at 100 dpi would give an image size of 600×400 pixels, nearly full screen on a 640×480 pixel screen, and too large and slow for web pages. This image was scanned at 200 dpi. The higher resolution shows a bit more detail, but also magnifies the image size. The scan was cropped to a 356×280 pixel image. Scanned at 300 dpi, which is maximum optical resolution on the E3 scanner used. The image was cropped to maintain the same 356×280 pixel size. It’s certainly larger, but it’s very
